1. Field of the Invention
With regard to the classification of art, this invention is believed to be found in the general class entitled "Material or Article Handling", and more particularly to an apparatus for lifting a container by way of a telescoping tubular column.
2. Description of the Prior Art The lifting of receptacles, containers, drums and the like are the subject of several U.S. patents. The closest known art related to the present invention are U.S. Pat. No. 4,797,050 issued to Habicht on Jan. 10, 1989 and U.S. Pat. No. 5,205,699 issued to Habicht on Apr. 27, 1993. Each of the listed patents is soley owned by a co-inventor and owner of the present invention. These patents are included by reference to the extent that the law allows.
Each of the prior U.S. patents teaches the use of a linear actuator for providing the lifting of the container. These prior art patents generally require that the linear actuator be powered by a compressed fluid. One of the disadvantages of using a linear actuator is that after a period of time leakage may occur at the piston and/or piston rod seal. Many times this leakage results in the contamination of the environment in which the apparatus is used. Any leakage also results in the consumption of power, additional to that which is required to perform the intended task. Another disadvantage associated with using a linear actuator is safety. It is necessary to provide a separate safety device or lock for ensuring the safety of workers in the vicinity of an apparatus employing a linear actuator.
The present invention overcomes the disadvantages recited above.